CALIFORNIA · ALAMEDA COUNTY

Oakland trades hurricane wind for the Hayward Fault and the Bay breeze

On the East Bay shore of San Francisco Bay, Oakland is a low-wind, seismic-dominated city — design under the CBC and ASCE 7-22, where the fault, not the gust, sizes the frame.

90–100MPH BASIC WIND · RISK II
B / CEXPOSURE · URBAN / BAY
CBC+ TITLE 24 · ASCE 7-22
SDC D–ESEISMIC DOMINATES

CYAN · WHY OAKLAND IS A LOW-WIND CITY

Sheltered by the Peninsula, ruled by the fault beneath the hills

The San Francisco Peninsula blunts the open-Pacific gust, so Oakland's basic wind sits in the 90–100 mph band (Risk II, 3-second gust) — moderate, while seismic carries the lateral system.

Bay-front exposure

West Oakland, Jack London Square and the Port face open San Francisco Bay — Exposure C, higher pressures than inland B.

EXPOSURE C

Hills speed-up

The Oakland and Berkeley hills rise past 1,500 ft; ridgeline and escarpment sites take a topographic Kzt above 1.0 (ASCE 7-22 §26.8).

Kzt > 1.0

Hayward Fault runs through it

The active Hayward Fault crosses Oakland, placing it in Seismic Design Category D–E. Seismic lateral demand routinely outweighs wind.

SDC D–E

Wind still sizes cladding

Even where seismic governs the frame, wind controls C&C — windows, curtain wall, roofing — so the calc stays mandatory for permit.

C&C GOVERNS

Quick facts. Basic wind speed 90–100 mph (Risk II) · Risk III ~105–115 mph · Risk IV ~115–125 mph · Exposure B inland / C at the bay · CBC + Oakland Title 15 amendments + Title 24 · ASCE 7-22 · Alameda County · seismic typically governs the structure.

VIOLET · RISK CATEGORY & SPEED MAP

Higher risk category reads a longer-return-period map

Per ASCE 7-22 Table 1.5-1 each risk category selects a different basic-wind-speed map — a longer mean recurrence interval, not a fixed multiplier.

Risk CategoryOakland Basic WindTypical Occupancy
I · 300-yr map~85–95 mphAgricultural, minor storage, temporary structures
II · 700-yr map90–100 mphHomes, retail, offices, most standard occupancy
III · 1,700-yr map~105–115 mphSchools, assembly >300, substantial-hazard facilities
IV · 3,000-yr map~115–125 mphHospitals, fire/police, emergency shelters, EOCs

CYAN · WHAT A COMPLIANT OAKLAND CALC NEEDS

From the Port waterfront to the Montclair ridgeline

Six checkpoints that separate an approvable Oakland submittal from a returned one — geography drives every one.

Port of Oakland

Ship-to-shore cranes, warehouses and terminals on open bay take Exposure C and often dynamic / wind-tunnel review.

EXPOSURE C

Hills topography

Skyline Blvd, Grizzly Peak and Montclair sit on crests — apply Kzt, never assume flat terrain (§26.8).

Kzt CHECK

B / C transition

Between urban inland and bay shoreline, upwind roughness shifts — assess fetch per §26.7, don't default to B.

FETCH STUDY

Seismic + wind both

Hayward Fault drives SDC D–E; run both load cases and design each element for whichever governs.

DUAL CASE

CBC + Title 24

California Building Code with Oakland Title 15 amendments; Title 24 energy rules apply to every project.

CBC

CA PE-stamped

A California-licensed PE/SE stamps the calc; the Oakland Building Dept plan-reviews before permit.

PE / SE

VIOLET · EAST BAY VS THE PENINSULA

How Oakland reads against San Francisco across the bay

RequirementOaklandSan Francisco
Basic wind speed90–100 mph100–115 mph (ocean exposure)
ExposureB / C (urban / bay)B / C / D (adds ocean)
TopographyOakland Hills need KztSF hills need Kzt
Port facilitiesMajor port (Exposure C)Limited port
Governing loadSeismic — Hayward FaultSeismic — San Andreas
CodeCBC + Oakland amendmentsCBC + SF amendments

CYAN · OFFICIAL ALAMEDA COUNTY RESOURCES

Permit and licensing references for Oakland projects

Neighborhoods run from sea-level flats to 1,500-ft ridges — West Oakland and the Port use C, downtown and Lake Merritt use B, Montclair adds topography.

EMERALD · RUN THE OAKLAND NUMBERS

Calculate Oakland wind loads — bay, hills and fault accounted for

Enter an Oakland ZIP or address and get the 90–100 mph velocity, Exposure B/C, Oakland Hills Kzt and PE-ready ASCE 7-22 output for Building Department submittal.